I've started coming across instances where pets in a concentrated area suddenly just don't exist at all.

Earlier today, I flew over an area in Felwood where I saw some Minfernals pop up on the minimap. Later, I went and flew over, and every single one was gone. I could not find any single Minfernal in the zone any longer.

Back when pet battles were first released, plenty of Silithid Hatchlings decided to hang out around the Gaping Chasm in Tanaris. I caught three of them easily. I just flew over Tanaris and there isn't a single one to be found anywhere at all.

A couple of patches ago, Qiraji Guardlings were implemented. There were many of them just hanging out around the Scarab Wall. Today I went back and only found a single one within the Fallen Kingdom area, completely stuck within a wall.

I know there are some phasing issues with wild pets at the moment. Could it have something to do with these, or did all of these pets suddenly decide to become extremely rare and/or simply never respawn if caught?

* I didn't post this on the bug report forum because I can't tell if this is intentional or not.

** I'm pretty sure this is a phasing problem. A good example is Twilight Iguanas at the Twilight Bulwark in Thousand Needles. I can see a few iguanas when I'm technically in the Tanaris region on the edge, but once I go into the Bulwark they simply phase out. I've found a single one in the actual Twilight Bulwark area.